Aerosol jet printing is an emerging additive manufacturing, direct-write materials deposition method. Unlike other direct-write printing methods such as syringe/extrusion and ink-jet printing, aerosol-jet printing can be performed with a working distance in the range of 1-5 mm. Therefore, the quality of a printed feature is much less dependent on the topology of the surface onto which the ink is deposited/printed. With aerosol-jet printing the ink stream width also can be controlled from approximately 10 μm up to 200 μm and, for high volume systems, into the millimeter range.
Prior art approaches have included measuring material output by printing some amount of ink into a weighing pan over a given time and weighing the result. The deposition rate may then be calculated by noting what weight of ink is deposited per unit time, and determining the volume of the deposited ink based on the weight of the deposited ink and a known density of the deposited ink. This approach has several drawbacks. One drawback is that the process can be awkward and time-consuming. The weighing pan must be installed, the filling performed, the weighing pan removed, and then weighed. Furthermore, the printing into the weighing pan must be performed for a certain minimum period of time in order to deposit a certain minimum amount of ink, in order to provide reasonable accuracy to deposition rate calculations based on the elapsed time and total weight. At small scales, with small deposition rates, it may take a while to complete this process—as much as between a half an hour and an hour, with even some of the fastest deposition rates requiring on the order of ten minutes. Furthermore, this process may need to be repeated from start to finish several times to account for variability in the flow rate and uncertainty in the measurements.